1. Field of the Invention
This invention is directed to a tamper evident cap assembly that is connectable to a fluid loaded syringe in protective, sealing relation to a nozzle and discharge port of the syringe. A body includes a flow restricting member interconnected to define a one piece construction of the cap assembly. The flow restricting member is structured to facilitate a snap-fit connection of the cap assembly on the syringe, thereby sealing the discharge port thereof. Tampering is indicated by a separation of the flow restricting member and the body and a detachment of the body from the syringe when a predetermined force, sufficient to remove the body from the syringe, is exerted on the body.
2. Description of the Related Art
In hospitals or other medical care facilities, it is common for authorized medical personnel to order that a patient be given a drug or medication by injection. As a result, a number of syringes may be pre-loaded or filled by a pharmacist or other authorized personnel within the hospital or other facility, at a location which may be generally referred to as a syringe filling station. However, such a syringe filling station is typically located in a remote part of the facility, relative to the patient care area where the injection is to be administered. Indeed, at large medical facilities, a syringe filling station may resemble a factory on the hospital grounds from which drug loaded syringes are delivered to multiple nurse's stations in multiple other hospital buildings. Because of the remote location of many nurse's stations, relative to a syringe filling station, a loaded syringe is very often given to another person for delivery to a nurse's station for subsequent dosing of the patient by a duly qualified nurse or other medically trained person.
Also, especially in the case of a very expensive drug or an addictive type of drug that has been prescribed, such as but not limited to morphine, there is a danger that the pre-loaded syringe will be tampered with at some point, by a person seeking to improperly gain unauthorized access to the contents thereof. This possibility can present real danger if such person were to gain access to the prescribed medicine and then, inappropriately and without concern, substitute some other, unauthorized material in the syringe which looks like the actual prescribed medicine and dosage. By way of an example only, if saline solution were substituted for a dose of morphine, this could have extremely serious consequences. Thus, there is a problem of knowing if a sealed, preloaded syringe has, or has not, been exposed to contamination or might otherwise have been compromised by it being tampered with. This and related types of problems have been described in the inventor's own previously granted U.S. Pat. No. 4,667,837 and in other patents, such as U.S. Pat. No. 5,328,474.
However, certain problems remain in the relevant field of art, despite the introduction of products according to those two patents. These include problems of manufacturing such products in a manner which is relatively easy and inexpensive, as well as some problems involved with the assembly and placement onto a drug loaded syringe, such as at a drug filling station. Other problems exist relative to maintaining the sterility during storage at the manufacturing facility of the end caps, and during transport of them to another medical facility, and during storage of them at a medical facility. In summary, the present invention seeks to, address such problems and others associated with the handling of tamper evident end caps during the manufacturing of them, assembly of them and/or use at different stations and/or by different persons.
Accordingly, there is a need in this area for an improved, tamper evident, end cap assembly which is capable of being used with standard or conventional pre-loaded syringes in a manner which overcomes problems and or disadvantages of the type set forth above. If any such improved end cap assembly were developed, it would preferably have certain structural and operative features such as, but not limited to, being at least initially of a one piece construction in order to facilitate appropriate connection to a preloaded syringe. In addition, if any such improved end cap assembly were developed, it would preferably also be structured to provide a clear and unmistakable indication of tampering or of previous access to the contents of the preloaded syringe. Finally, if any such improved, tamper evident end cap assembly were developed, it would ideally also be structurally and operatively reliable, while still remaining relative easy and cost effective to make and assemble, in order to facilitate widespread use and acceptance through out the medical profession.